The present invention relates generally to the field of automated test equipment for performing operational testing on electronic components. More particularly, the present invention relates to a testing system that automatically monitors operational testing of electronic entertainment devices, including compact disc players and tape players, without human supervision and that suppresses spurious error signals generated at the end of a testing cycle.
There is a need for a testing system that will give a manufacturer or repair service confidence that an electronic component will not be subject to intermittent failures.
Intermittent failures are, by their nature, difficult to detect. To test for freedom from such failures, a unit under test (UUT)is operated for a length of time and flaws in the reproduced signal are tallied. If the number of detected flaws is low enough so that the statistical probability of an intermittent failure is acceptable, the equipment is sold or returned to service.
This type of testing requires that the equipment be connected to a testing apparatus for a relatively long period of time, perhaps hours or days. During this period the equipment must be monitored and any errors generated by the equipment logged for later analysis.
For components that play back recorded media, such as compact disc players, testing requires that a test media with a prerecorded signal be loaded into the device. The prerecorded media is then played back repeatedly. Noises generated at the end of a playback cycle, while the optical head is retracting, may result in the logging of spurious errors. To prevent these spurious errors from being counted as flaws the logging system must be reset after each playback cycle.
Resetting the logging system requires the attention of a technician and adds to the cost of the goods or to the cost of repair. In addition, because human intervention is periodically required, testing equipment at facilities that do not operate around the clock is idle after work hours. This represents an additional cost in terms of capital equipment.
For components that have a large number of operational modes, testing for intermittent errors can be laborious. For example, radio receivers typically receive signals across a wide spectrum of frequencies and may use two or three reception modes, i.e., AM, FM, Shortwave. Each mode may need to be tested at several frequencies to assure that intermittent failures will not occur. A testing procedure for such a device requires that a technician be on hand throughout the testing period to reset the UUT and the testing signal generator for each of the tested modes. In addition, error logging must be disabled while the TUT and signal generator are reset to prevent the logging of spurious errors.
There is a need, therefore, for an automated test system for testing electronic devices that can monitor a UUT and track its error history automatically. Automated testing would reduce repair costs by allowing a technician to test a number of devices simultaneously.
The need for automated testing is particularly great in the field of high-volume consumer electronics, for example compact disc players. These devices incorporate delicate mechanical systems that are prone to intermittent failures. Further, these devices are sold in a competitive marketplace that demands lower prices and improved reliability.